From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1XqKKx-00046G-Og for mharc-qemu-trivial@gnu.org; Mon, 17 Nov 2014 06:19:15 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53223) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqKKr-00040O-UC for qemu-trivial@nongnu.org; Mon, 17 Nov 2014 06:19:14 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XqKKn-0005d4-4X for qemu-trivial@nongnu.org; Mon, 17 Nov 2014 06:19:09 -0500 Received: from szxga03-in.huawei.com ([119.145.14.66]:15461) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqKKc-0005al-9I; Mon, 17 Nov 2014 06:18:55 -0500 Received: from 172.24.2.119 (EHLO szxeml413-hub.china.huawei.com) ([172.24.2.119]) by szxrg03-dlp.huawei.com (MOS 4.4.3-GA FastPath queued) with ESMTP id AXF85250; Mon, 17 Nov 2014 19:18:49 +0800 (CST) Received: from [127.0.0.1] (10.177.19.102) by szxeml413-hub.china.huawei.com (10.82.67.152) with Microsoft SMTP Server id 14.3.158.1; Mon, 17 Nov 2014 19:18:41 +0800 Message-ID: <5469D98A.8020408@huawei.com> Date: Mon, 17 Nov 2014 19:18:34 +0800 From: Gonglei User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:11.0) Gecko/20120327 Thunderbird/11.0.1 MIME-Version: 1.0 To: Paolo Bonzini References: <1416046008-7880-1-git-send-email-arei.gonglei@huawei.com> <1416046008-7880-10-git-send-email-arei.gonglei@huawei.com> <5469D4C4.5090407@redhat.com> In-Reply-To: <5469D4C4.5090407@redhat.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.19.102] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020203.5469D999.0129, ss=1, re=0.001, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: a1a71920f2c02b347e704da5364cf20d X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-Received-From: 119.145.14.66 Cc: "Huangweidong \(C\)" , Zhanghailiang , "qemu-trivial@nongnu.org" , "mjt@tls.msk.ru" , "qemu-devel@nongnu.org" , "Huangpeng \(Peter\)" , Gerd Hoffmann Subject: Re: [Qemu-trivial] [PATCH 9/9] hcd-musb: fix dereference null return value X-BeenThere: qemu-trivial@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 17 Nov 2014 11:19:14 -0000 On 2014/11/17 18:58, Paolo Bonzini wrote: > > > On 15/11/2014 11:06, arei.gonglei@huawei.com wrote: >> From: Gonglei >> >> Signed-off-by: Gonglei >> --- >> hw/usb/hcd-musb.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/hw/usb/hcd-musb.c b/hw/usb/hcd-musb.c >> index 66bc61a..f2cb73c 100644 >> --- a/hw/usb/hcd-musb.c >> +++ b/hw/usb/hcd-musb.c >> @@ -624,6 +624,10 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, >> >> /* A wild guess on the FADDR semantics... */ >> dev = usb_find_device(&s->port, ep->faddr[idx]); >> + if (!dev) { >> + TRACE("Do not find an usb device"); >> + return; >> + } >> uep = usb_ep_get(dev, pid, ep->type[idx] & 0xf); >> usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, >> (dev->addr << 16) | (uep->nr << 8) | pid, false, true); >> > > I think this patch is not the real fix. usb_ep_get and > usb_handle_packet can deal with a NULL device, but we have to avoid > dereferencing NULL pointers when building the id. > Good catch :) > Paolo > > diff --git a/hw/usb/hcd-musb.c b/hw/usb/hcd-musb.c > index 66bc61a..40809f6 100644 > --- a/hw/usb/hcd-musb.c > +++ b/hw/usb/hcd-musb.c > @@ -608,6 +608,7 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, > USBDevice *dev; > USBEndpoint *uep; > int idx = epnum && dir; > + int id; > int ttype; > > /* ep->type[0,1] contains: > @@ -625,8 +626,11 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, > /* A wild guess on the FADDR semantics... */ > dev = usb_find_device(&s->port, ep->faddr[idx]); > uep = usb_ep_get(dev, pid, ep->type[idx] & 0xf); > - usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, > - (dev->addr << 16) | (uep->nr << 8) | pid, false, true); > + id = pid; > + if (uep) { > + id |= (dev->addr << 16) | (uep->nr << 8); > + } > + usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, id, false, true); > usb_packet_addbuf(&ep->packey[dir].p, ep->buf[idx], len); > ep->packey[dir].ep = ep; > ep->packey[dir].dir = dir; This is a good approach, id is just a identifying. Thanks, Best regards, -Gonglei From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53199) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqKKi-0003oV-4B for qemu-devel@nongnu.org; Mon, 17 Nov 2014 06:19:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XqKKd-0005bh-Ak for qemu-devel@nongnu.org; Mon, 17 Nov 2014 06:19:00 -0500 Message-ID: <5469D98A.8020408@huawei.com> Date: Mon, 17 Nov 2014 19:18:34 +0800 From: Gonglei MIME-Version: 1.0 References: <1416046008-7880-1-git-send-email-arei.gonglei@huawei.com> <1416046008-7880-10-git-send-email-arei.gonglei@huawei.com> <5469D4C4.5090407@redhat.com> In-Reply-To: <5469D4C4.5090407@redhat.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 9/9] hcd-musb: fix dereference null return value List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: "Huangweidong (C)" , Zhanghailiang , "qemu-trivial@nongnu.org" , "mjt@tls.msk.ru" , "qemu-devel@nongnu.org" , "Huangpeng (Peter)" , Gerd Hoffmann On 2014/11/17 18:58, Paolo Bonzini wrote: > > > On 15/11/2014 11:06, arei.gonglei@huawei.com wrote: >> From: Gonglei >> >> Signed-off-by: Gonglei >> --- >> hw/usb/hcd-musb.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/hw/usb/hcd-musb.c b/hw/usb/hcd-musb.c >> index 66bc61a..f2cb73c 100644 >> --- a/hw/usb/hcd-musb.c >> +++ b/hw/usb/hcd-musb.c >> @@ -624,6 +624,10 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, >> >> /* A wild guess on the FADDR semantics... */ >> dev = usb_find_device(&s->port, ep->faddr[idx]); >> + if (!dev) { >> + TRACE("Do not find an usb device"); >> + return; >> + } >> uep = usb_ep_get(dev, pid, ep->type[idx] & 0xf); >> usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, >> (dev->addr << 16) | (uep->nr << 8) | pid, false, true); >> > > I think this patch is not the real fix. usb_ep_get and > usb_handle_packet can deal with a NULL device, but we have to avoid > dereferencing NULL pointers when building the id. > Good catch :) > Paolo > > diff --git a/hw/usb/hcd-musb.c b/hw/usb/hcd-musb.c > index 66bc61a..40809f6 100644 > --- a/hw/usb/hcd-musb.c > +++ b/hw/usb/hcd-musb.c > @@ -608,6 +608,7 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, > USBDevice *dev; > USBEndpoint *uep; > int idx = epnum && dir; > + int id; > int ttype; > > /* ep->type[0,1] contains: > @@ -625,8 +626,11 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, > /* A wild guess on the FADDR semantics... */ > dev = usb_find_device(&s->port, ep->faddr[idx]); > uep = usb_ep_get(dev, pid, ep->type[idx] & 0xf); > - usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, > - (dev->addr << 16) | (uep->nr << 8) | pid, false, true); > + id = pid; > + if (uep) { > + id |= (dev->addr << 16) | (uep->nr << 8); > + } > + usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, id, false, true); > usb_packet_addbuf(&ep->packey[dir].p, ep->buf[idx], len); > ep->packey[dir].ep = ep; > ep->packey[dir].dir = dir; This is a good approach, id is just a identifying. Thanks, Best regards, -Gonglei